The invention is generally directed to toner and developer compositions, and more specifically, the present invention is directed to developer and toner compositions containing certain resins and optional charge enhancing additives, which impart or assist in imparting a positive charge to the toner resin particles, and enable toners with rapid admix characteristics, stable triboelectric characteristics in embodiments, and wherein the fusing properties of the toner resin are relatively constant in embodiments. In embodiments, there are provided in accordance with the present invention toner compositions comprised of certain substituted polyoxazoline polymers as resin particles, and pigment particles. In one embodiment, the present invention is directed to toners comprised of substituted polyoxazoline polymers of the formulas illustrated herein, which polymers have excellent glass transition temperatures, and suitable molecular weights and pigment particles, like carbon black, magnetite, cyan, yellow, magenta, red, green, blue, and the like. The polymers selected in embodiments possess a glass transition temperature or a crystalline melting temperature of from about 55 to about 75.degree. C., a melt fusing temperature of from about 180.degree. F. to about 300.degree. F., and a hot offset temperature of from about 230.degree. F. to about 380.degree. F. The fusing temperatures were determined using a Xerox Corporation 5028 silicone roll fuser operated at 3.1 inches per second with solid area prints (toner mass area is 1.1 to 1.3 milligrams/cm.sup.2) to the crease 20 fix level relative to the Xerox Corporation 1075 crease fix standards. This test condition correlates to the minimum fix temperature at the 65 crease level obtained with a Xerox Corporation 1075 fuser operated at 11 inches per second. The crease test consists of folding a solid area print with between 1.1 and 1.3 milligram/cm.sup.2 toner mass area onto itself (180.degree. bend), and then the print is unfolded and the optical density of the toner in the region of the crease is measured and correlated in the Xerox Corporation 1075 machine. The toner compositions of the present invention in embodiments thereof maintain their triboelectric charging characteristics for an extended number of imaging cycles, exceeding, for example, 500,000. The toner and developer compositions of the present invention can be selected for electrophotographic, especially xerographic, imaging and printing processes, including color processes.
Developer and toner compositions, including those with charge enhancing additives, which impart a positive charge to the toner resin, are well known. Thus, for example, there is described in U.S. Pat. No. 3,893,935 the use of quaternary ammonium salts as charge control agents for electrostatic toner compositions. In this patent, there are disclosed quaternary ammonium compounds with four R substituents on the nitrogen atom, which substituents represent an aliphatic hydrocarbon group having 7 or less, and preferably about 3 to about 7 carbon atoms, including straight and branch chain aliphatic hydrocarbon atoms, and wherein X represents an anionic function including, according to this patent, a variety of conventional anionic moieties such as halides, phosphates, acetates, nitrates, benzoates, methylsulfates, perchlorides, tetrafluoroborates, benzene sulfonates, and the like. In U.S. Pat. No. 4,221,856 there are disclosed electrophotographic toners containing resin compatible quaternary ammonium compounds in which at least two R radicals are hydrocarbons having from 8 to about 22 carbon atoms, and each other R is a hydrogen or hydrocarbon radical with from 1 to about 8 carbon atoms, and A is an anion, for example sulfate, sulfonate, nitrate, borate, chlorate, and the halogens such as iodide, chloride and bromide, reference the Abstract of the Disclosure and column 3; a similar teaching is presented in U.S. Pat. No. 4,312,933 which is a division of U.S. Pat. No. 4,291,111; and similar teachings are presented in U.S. Pat. No. 4,291,112 wherein A is an anion including, for example, sulfate, sulfonate, nitrate, borate, chlorate, and the halogens. There are also described in U.S. Pat. No. 2,986,521 reversal developer compositions comprised of toner resin particles coated with finely divided colloidal silica. In these and other patents, the toner resin includes, for example, styrene acrylates, styrene methacrylates, styrene butadienes, polyesters, polyamides, and the like. Advantages of the toner resins of the present invention as compared, for example, to the aforementioned styrene methacrylates include a low melt fusing temperature (10 to 130.degree. F. lower than Xerox Corporation 1075 toner with a styrene methacrylate resin), broad fusing latitudes (50 to 80.degree. F. compared with 35.degree. F. of a Xerox Corporation toner control 1075), hot roll fusing without the need for silicone fuser oil release agents, color compatibility toner jettability, and the potential for negative as well as positive toner tribocharging. Moreover, these resin materials can serve as additives to conventional toners to aid in effective fused toner release from fuser rolls and to promote toner charging.
Also, there are disclosed in U.S. Pat. No. 4,338,390, the disclosure of which is totally incorporated herein by reference, toner compositions comprised of styrene polymers, and containing as charge enhancing additives organic sulfate and sulfonates, which additives can impart a positive charge to the toner composition. Further, there is disclosed in U.S. Pat. No. 4,298,672, the disclosure of which is totally incorporated herein by reference, positively charged toner compositions with styrene polymers, resin particles and pigment particles, and as charge enhancing additives alkyl pyridinium compounds. Additionally, other documents disclosing positively charged toner compositions comprised of styrene polymers, pigments particles, and charge control additives include U.S. Pat. Nos. 3,944,493; 4,007,293; 4,079,014; 4,394,430 and 4,560,635 which illustrates a toner with a distearyl dimethyl ammonium methyl sulfate charge additive.
The following prior art, all U.S. patents, are mentioned: U.S. Pat. No. 4,812,381 which discloses toners and developers containing charge control agents comprising quaternary ammonium salts of the formula indicated, for example, in the Abstract of the Disclosure, wherein R is alkyl with from 12 to 18 carbon atoms, and the anion is a trifluoromethylsulfonate; a similar teaching is presented in U.S. Pat. Nos. 4,834,921; 4,490,455 which discloses toners with, for example, amine salt charge enhancing additives, reference the Abstract of the Disclosure for example, and wherein A is an anion including those derived from aromatic substituted sulfonic acids, such as benzene sulfonic acid, and the like, see column 3, beginning at line 33; U.S. Pat. No. 4,221,856 directed to toners with a quaternary ammonium compound wherein A is an anion such as sulfate, sulfonate, nitrate, borate, chlorate, and certain halogens, see the Abstract of the Disclosure; U.S. Pat. No. Reissue 32,883 (a reissue of U.S. Pat. No. 4,338,390) illustrates toners with sulfate and sulfonate charge additives, see the Abstract of the Disclosure, wherein R.sub.4 is an alkylene, and the anion contains an R.sub.5 which is a tolyl group, or an alkyl group of from 1 to 3 carbon atoms, and n is the number 3 or 4; U.S. Pat. No. 4,323,634 which discloses toners with charge additives of the formulas presented in column 3, providing that at least one of the R's is a long chain amido group, and X is a halide ion or an organo sulfur containing group; U.S. Pat. No. 4,326,019 relating to toners with long chain hydrazinium compounds, wherein the anion A can be a sulfate, sulfonate, phosphate, halide, nitrate, see the Abstract of the Disclosure for example; U.S. Pat. No. 4,752,550 which illustrates toners with inner salt charge additives, or mixtures of charge additives, see for example column 8; U.S. Pat. No. 4,684,596 which discloses toners with charge additives of the formula provided in column 3 wherein X can be a variety of anions such as trifluoromethane sulfonate, and U.S. Pat. Nos. 4,604,338; 4,792,513; 3,893,935; 4,826,749 and 4,604,338. The disclosures of each of the aforementioned patents are totally incorporated herein by reference.
Illustrated in U.S. Pat. No. 4,937,157, the disclosure of which is totally incorporated herein by reference, are toner compositions comprised of styrene acrylate, styrene methacrylate, styrene butadiene, polyester, and the like, resin particles, pigment, or dye, and tetraalkyl, wherein alkyl, for example, contains from 1 to about 30 carbon atoms, ammonium bisulfate charge enhancing additives such as distearyl dimethyl ammonium bisulfate, tetramethyl ammonium bisulfate, tetraethyl ammonium bisulfate, tetrabutyl ammonium bisulfate, and preferably dimethyl dialkyl ammonium bisulfate compounds where the dialkyl radicals contain from about 10 to about 30 carbon atoms, and more preferably dialkyl radicals with from about 14to about 22 carbon atoms, and the like.
Illustrative examples of known toner resins include polyamides, polyolefins, styrene acrylates, styrene methacrylates, styrene butadienes, crosslinked styrene polymers, polyamides, polyurethanes, vinyl resins, including homopolymers or copolymers of two or more vinyl monomers; and polyesters, such as those obtained from the polymeric esterification of a dicarboxylic acid and a diol comprising a diphenol. Vinyl monomers include styrene, p-chlorostyrene, unsaturated mono-olefins such as ethylene, propylene, butylene, isobutylene and the like; saturated mono-olefins such as vinyl acetate, vinyl propionate, and vinyl butyrate; vinyl esters like esters of monocarboxylic acids including methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, dodecyl acrylate, n-octyl acrylate, phenyl acrylate, methyl methacrylate, ethyl methacrylate, and butyl methacrylate; acrylonitrile, methacrylonitrile, acrylamide; mixtures thereof; and the like. Specific examples of toner resins include styrene butadiene copolymers with a styrene content of from about 70 to about 95 weight percent, reference the U.S. patents mentioned herein, the disclosures of which have been totally incorporated herein by reference. In addition, crosslinked resins, including polymers, copolymers, homopolymers of the aforementioned styrene polymers may be selected.
In a patentability search report, there were recited U.S. Pat. No. 4,880,857, wherein oxazoline groups in a toner are apparently disclosed, and also see column 6; U.S. Pat. Nos. 4,339,518 and 5,061,587.